Commitments and Contingencies: Supply Commitment (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Mar. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Undisbursed portion of construction loans in process (see Note 4)	$ 99,253	$ 100,719
Undisbursed lines of credit	138,711	120,918
Commitments to extend credit	41,218	34,962
Total commitments	$ 279,182	$ 256,599

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

No definition available.

Name:	us-gaap_OtherCommitment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant